Container and method of making same



Jan. 24, 1967 F. J. CLOSE CONTAINER AND METHOD OF MAKING SAME 2 Sheets-Sheet 1 Filed Oct. 12, 1964 O N! mJ M m 9 W Y B Qwyq.

ATTORNEY Jan. 24, 1967 v J, CLOSE 3,300,080

CONTAINER AND METHOD OF MAKING SAME Filed Oct. 12, 1964 2 Sheets-Sheet 2 l I I 111 H IM 1 w 12 I 20 Jig, 6 8 i0 III'I'I'III'I'IIII/l) 8 21 L5 13 IN VEN TOR. Frederick J 0089 ATTORNEY United States Patent C) 3,300,080 CONTAINER AND METHOD OF MAKING SA ME Frederick J. Close, Pittsburgh, Pa., assignor to Aluminum Company of America, Pittsburgh, Pa., a corporation of Pennsylvania Filed Oct. 12, 1964, Scr. No. 403,108 4 Claims. (Cl. 220-54) This invention relates to an impact extruded container with an opening tab and chime and to a method of producing the same. More particularly this invention relates to an impact extruded container with an opening tab attached to the container end wall having a tear-out section so that the container may be opened by exerting opening force on the attached tab without the use of a special opening tool, and having a chime to prevent accidental premature rupture of the scored tear-out section and to a method of making such container.

In a container incorporating an attached opening feature, it is often desirable to provide some means of preventing premature rupture of the score line defining the tear-out section. Premature rupture can be caused when the containers are stacked one on top of the other as in shipment or storage and force exerted on the top of the container by reason of the weight of the stacked containers or rough handling causes the attached opening tab to be depressed thereby rupturing the score line defining the tear-out section to which the tab is attached.

Prevention of premature rupture of containers incorporating an attached tab opening feature may be achieved by providing a rim or chime around the periphery of the container end wall so that the end wall with the attached opening tab is recessed below the upper portion of the container side wall. When containers with chimes are stacked, the container on top is supported by the chime of the container underneath thereby preventing sufficient force from being applied to the attached opening tab to cause the tear-out section to be ruptured.

It is an object of this invention to provide an impact extruded container having an opening tab feature, with a chime.

A further object of this invention is to provide an im pact extruded container having an opening tab attached to a scored tear-out section with a chime to prevent premature rupture of the score line.

This invention is utilized in connection with containers which are made by the well-known method of impact extrusion. Impact extrusion containers are made from a slug or blank of ductile metal that is placed in a recessed die of the outside diameter of the container to be formed.

A punch or inner die, of the internal shape and dimensions of the container to be formed, is forced against the blank or slug and into the recessed die.

As the punch is forced into the recessed die, it compresses the slug first into the space between the die and punch and then, upon further movement of the punch, causes some of the metal to flow through a narrow space or slot between the recessed die and the punch and along the punch in a thin, seamless shape to form the side wall of the container, with some of the metal being left at the bottom of the recessed die to form the end wall. The extruded container body is removed or stripped from the punch and the container completed by trimming, filling the container with the desired product and then sealing the open end by some suitable means.

Metals used in producing impact extruded containers are those metals or alloys which are capable of being deformed easily. Aluminum and aluminum base alloys have been found to be quite satisfactory for impact extruded containers, including those utilizing the present invention. As used herein the term aluminum includes 3,300,080 Patented Jan. 24, 1967 aluminum and aluminum base alloys containing at least fifty (50) percent by weight of aluminum.

To attach an opening tab to an impact extruded container, a rivet stud is provided in the end wall of the formed container body by providing a suitable cavity for the rivet stud in the recessed die and allowing the metal to flow into the cavity during the forming of the container body by impact extrusion. An apertured tab i placed on the container end Wall so that the rivet stud protrudes through and beyond the aperture in the tab and the rivet stud compressively upset or headed to 'bear upon the tab in firmly overlapping relationship thereby securely attaching the opening tab to the container.

The container end wall has a section defined by a score line or score lines, which is to be removed by the ultimate consumer to gain access to the container contents by exerting force on the opening tab to initially rupture the score line and to continue severance along the score line to remove the defined tear-out section. In some instances this tear-out section is a relatively small panel defined by one continuous score line. This type of tear-out section or panel is normally employed on containers used for liquids such as beverages. On the other hand, in the case of containers for solids or semisolids, a larger opening is usually desired to facilitate easy access to the contents, and a large tear-out panel to be removed may be defined either by one continuous score line or by a peripheral tear strip formed by two substantially parallel score lines.

In accordance with this invention, the impact extruded container is provided with an outwardly extending circumferential solid chime integral with the end wall and side wall of the container and perpendicular to the plane of the end wall. The chime is made by providing a suitable cavity in the recessed die and allowing the metal to flow into the cavity during the initial forming of the container body by extrusion. The word solid in respect of the chime means that the chime is formed from a mass of the metal during extrusion of the container and is not hollow such as in the case where the container is extruded without an outwardly extending chime and the container subsequently reformed to recess the end Wall below the upper portion of the side Wall.

An important advantage of this invention is that a solid chime for impact extruded containers with an opening tab feature, is provided at the same time as the container body is extruded. That is, the chime is an integral part of the container in the as-extruded condition. This eliminates any additional work handling that would be required if the end wall of the container were to be reformed to obtain a recessed end wall.

Another advantage of a solid chime for impact extruded containers is that'the chime in cross section is relatively narrow ascompared to that of a container that must be reformed'to obtain a recessed end wall. This invention allows the score. line to be nearer the outer edge of the end wall thus affording a tear-out panel of greater area.

The invention may be further understood from the following detailed description, referring to the accompanying drawings, in which:

FIG. 1 is a plan view of a top of a container utilizing the invention;

FIG. 2 is an enlarged fragmentary cross-sectional view of the container utilizing the invention taken on line 11-11 of FIG. 1;

FIG. 3 is a fragmentary cross-sectional view of a container utilizing the invention;

FIG. 4 is a plan view of a top of a container utilizing the invention with an alternate score configuration;

FIG. 5 is a schematic cross-sectional view showing forming the container body with an integral solid chime by impact extrusion;

FIG. 6 is a schematic cross-sectional view showing scoring the container;

FIG. 7 is a fragmentary cross-sectional view showing heading the rivet.

Referring to FIGS. 1 and 2 the container body 13 having an end wall 1 has an opening tab 2 securely attached to a tear-out section 3, defined by score line 6, in close proximity to the terminal end 4 of the tear-out section, by means of a solid rivet that is integral with the container end wall 1. The word solid in respect of the rivet means that the rivet either has no recess that opens towards the interior of the container, or if provided with any such recess, the recess is of such modest dimensions that there need be no interior supporting element within the recess during the heading operation. The headed portion 9 of the solid rivet 5 bears upon the tab in firmly overlapping relationship thereto. The scoring can vary from that shown in FIG. 1 and is not restricted to any particular tear-out configuration.

The opening tab 2 provides the gripping means for force to be manually exerted on the tear-out section 3 to rupture initially the container end wall 1 at the terminal end 4 of the tear-out section 3 and to continue severance along the score line 6, for removal of the tearout section from the container member. The opening tab 2 may be either the flexible inelastic type or the rigid lever type. A rigid lever opening tab with reinforcing ribs 11 is shown in FIGS. 1 and 2. The tab 2 may, if desired, have an upturned end 14 to afford greater ease is gripping the tab. The size of the aperture of the tab in relation to the rivet stud dimensioned is such that the tab fits easily over the rivet stud without a looseness of adegree that impairs a firm overlapping bearing of the rivet head upon the tab. The rivet is headed by supporting the end wall on the interior side of the container in the area of the rivet and compressively upsetting in any conventional manner the rivet end that protrudes beyond the tab.

An outwardly extending circumferential'solid chime 7 is formed at the periphery of the container end wall 1 at the same time as the impact extruder container body is I formed, and is integral with both the end wall 1 and side wall and substantially perpendicular to the plane of the end wall 1. The chime 7 should be of sufiicient height to extend above the attached opening tab 2 and rivet 5 so that the chime will prevent interference of the opening tab and rivet in stacking of containers and help to prevent premature rupture of the scored tear-out section when containers are so stacked.

FIG. 3 shows a cross-sectional view of the shape of the impact extruded container body 13 having an end wall 1 with an integral rivet stud 8, a side wall 10 and the solid chime 7 integral with the side wall and the end wall, prior to scoring and attaching the opening tab. The upper portion of the rivet stud 8 shown in FIG. 3 has a cavity 12 that opens toward the exterior of the end wall; however, the rivet stud may be formed without such. The heading of a rivet with a cavity is somewhat easier and yet a sufiiciently strong jointure between the opening tab and the container is accomplished. The rivet stud 8 is of sufiicient height to protrude through and beyond the aperture in the opening tab and then be headed to attach securely the tab to the container with firm overlapping relationship of the rivet head to the tab.

The solid chime of the container body 13 shown in FIG. 3 is achieved by providing a suitable recessed die cavity shape so that in the formation of the container body by impact extrusion the metal will flow into the die cavity and thus form a solid chime on the container body at the same time as the rest of the container body is formed.

Scoring of the container end wall after it has been impact extruded, may be done in a convenitonal manner and is usually done prior to placing the tab on the container end wall for attachment. The rivet stud 8 is usually located in close proximity to the terminal end 4 of the tear-out section, and is within the score lines 6 which form the tear-out section.

FIG. 4 shows one of many alternate forms of tearout sections applicable to the impact extruded container end wall 1. The container end wall 1 is scored or weakened along the lines 6 to form a tear-strip 3 that extends around the container end wall 1 near the circumferential soli-d chime 7. Thus, severance and removal of the tear-strip removes a substantial portion of the container end Wall 1 allowing access to the packaged contents. This tear-out section is particularly useful for packaging solids or semi-solids. The scoring can vary from that shown in FIG. 4 and is not restricted to any particular tear-strip configuration. As shown in FIG. 4, the opening tab 2, shown as a rigid lever type with reinforcing ribs 11 and upturned end 14, is attached to the tear-strip 3, in close proximity to the terminal end 4, by means of a solid headed integral rivet 5.

Referring to FIGS. 5 to 7 there is illustrated schematically various stages in producing an impact extruded container with an attached opening tab end having an integral solid chime in accordance with the invention.

FIG. 5 shows the completed forming step of the impact extruded container body. Recessed die 15, having a cavity dimensioned to the outside diameter of the container body 13, and a punch 16, having the internal shape and dimensions of the container body 13, are shown in the closed position. The solid outwardly extending circumferential chime 7 is made by providing a suitable cavity 18 in the recessed die 15 which allows the metal to flow into the cavity during the forming of the container body 13. The chime thus formed is integral with the side wall 10 and end wall 1 of the container body 13 and is substantially perpendicular to the plane of the end wall. The rivet stud 8 in the end wall 1 is also formed by the metal flowing into a suitable cavity 17 in the recessed die 15. After forming of the container body is complete, it is stripped from the punch and trimmed.

FIG. 6 schematically illustrates scoring the container end wall to provide a tear-out section. Scoring of the container end wall is done in a conventional manner, and is usually done prior to placing the tab on the container end wall for attachment. The rivet stud 8 is located Within the tear-out section and usually in close proximity to the terminal end thereof.

The scoring die 19 carries a suitable scoring projection 20 so that when the die 19 and mandrel 21 are closed, with the container 13 therebetween, the desired score configuration and depth will be achieved on the container end wall 1. The dimensions of the score projection 20 to achieve the desired shape and depth of the score will depend upon the metal used and the type of product to be packaged in the container.

FIG. 7 shows the rivet heading operation to attach the opening tab 2 to the container end wall 1. Prior to heading, the apertured opening tab is superimposed over the container end wall so that the rivet stud protrudes through the aperture in the tab. The mandrel 21 supports the interior of the container end wall at the rivet area. When the cooperating die 22 is closed to compressively upset the rivet, the rivet end protruding beyond the tab forms the headed portion 9 of the rivet 5 which overlies the P ph ry of the aperture in the tab and securely attaches the tab to the container in firm relationship.

The description in specific detail of the selected practice of the invention will suggest to those skilled in the art, various changes, substitutions and other departures from my disclosure within the spirit and scope of the appended claims.

What is claimed is: 1. In a method of making an easy opening metal container having a rivet attached opening tab, the steps of;

impact extruding a body having a side wall, one end wall, a solid rivet stud projecting outwardly from said end wall, and an outwardly extending circumferential solid chime integral with said side wall and said end wall and substantially perpendicular to the plane of the end wall,

scoring said end wall to provide a tear-out section therein,

placing upon said end wall an opening tab having a rivet receiving aperture so that said rivet stud protrudes through and beyond said aperture, and

heading said rivet stud into firm overlapping relationship with said tab to attach the same to said end wall.

2. In a method of making an easy opening aluminum container having a rivet attached opening tab, the steps of;

impact extruding a body having a side wall, one end wall, a solid rivet stud projecting outwardly from said end wall, and an outwardly extending circumferential solid chime integral with said side wall and said end wall, said chime being substantially perpendicular to the plane of the end wall,

scoring said end wall to provide a tear-out section therein,

placing upon said end wall an opening tab having a rivet receiving aperture so that said rivet stud protrudes through and beyond said aperture, and

heading said rivet stud into firm overlapping relationship with said tab to attach the same to said end wall.

3. An impact extruded container, comprising:

a body having an integral side wall and end Wall, said end wall provided with a score line to define a tearout section,

an apertured opening tab attached to the said tear-out section by a solid headed rivet integral with the said end wall, and

an outwardly extending circumferential solid chime integral with .the end wall and side wall, said chime being substantially perpendicular to the plane of the end wall and extending above the attached opening tab.

4. An impact extruded aluminum container, compris- 10 ing:

References Cited by the Examiner UNITED STATES PATENTS 4/1955 Schlabach et al. 22027 5/1959 Kelemen 29522 4/1965 Zundel 22054 6/1965 Fraze 11312l 8/1965 Fraze 113-121 THERON E. CONDON, Primary Examiner.

G. T. HALL, Examiner. 

4. AN IMPACT EXTRUDED ALUMINUM CONTAINER, COMPRISING: A BODY HAVING AN INTEGRAL SIDE WALL AND END WALL, SAID END WALL PROVIDED WITH A SCORE LINE TO DEFINE A TEAROUT SECTION, AN APERTURED OPENING TAB ATTACHED TO THE SAID TEAR-OUT SECTION BY A SOLID HEADED RIVET INTEGRAL WITH THE SAID END WALL, AND AN OUTWARDLY EXTENDING CIRCUMFERENTIAL SOLID CHIME INTEGRAL WITH THE END WALL AND SIDE WALL, SAID CHIME BEING SUBSTANTIALLY PERPENDICULAR TO THE PLANE OF THE END WALL AND EXTENDING ABOVE THE ATTACHED OPENING TAB. 